Generate static library written in golang

[sari...@gmail.com]

Hello,

go version go1.4 darwin/amd64

I'm trying to create a static library written in golang, then using that static library in a c/obj/xcode project. 

== gittu.go ==

package gittu

import "C"

//export getGittu

func getGittu() *C.char {

s := "Hello Gittu"

return C.CString(s)

}

==

After that i use "go install" to generate a gittu.a in $GOPATH/pkg/darwin_amd64/..............

But when i include that gittu.a in xcode, i get this error,

ignoring file /usr/local/Cellar/go/1.4/packages/pkg/darwin_amd64/github.com/sarim/gittu.a, file was built for archive which is not the architecture being linked (x86_64)

I manually tried to run cc, but still the same error. Any idea how to generate x86_64 static lib?

[David Crawshaw]

You cannot do that with Go 1.4.

In Go 1.5 there will be -buildmode=c-archive which will generate an
archive you can link into a C program as you've described. Details are
in the Go execution modes doc:
https://docs.google.com/document/d/1nr-TQHw_er6GOQRsF6T43GGhFDelrAP0NqSS_00RgZQ/edit?pli=1

You may also be interested in
http://tip.golang.org/misc/cgo/testcarchive/ as an example.

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[Ian Lance Taylor]

In Go 1.4, you can't.

In Go 1.5, you should be able to use go build -buildmode=c-archive.
It might be worth trying that now with the development version of Go,
to see if it works for you.

Ian

[Carlos Castillo]

Will the alternate build/link modes be supported for darwin in 1.5? AFAIK they haven't been implemented in OSX yet, and the OP is using OSX (according to his message).

[Ian Lance Taylor]

On Wed, Jun 3, 2015 at 2:13 PM, Carlos Castillo <cook...@gmail.com> wrote:
> Will the alternate build/link modes be supported for darwin in 1.5? AFAIK
> they haven't been implemented in OSX yet, and the OP is using OSX (according
> to his message).

The c-archive mode, which is the one I mentioned, is already supported
and working on Darwin.

The c-shared and shared modes do not yet work on Darwin. They are
more complicated than c-archive. I don't know if anybody is working
on them, but it would be great if they could.

Ian

[Alexandre Fiori]

This is cool stuff, I was playing with it a few days ago after watching Andrew's presentation.

Uploaded to GitHub so it may serve as an example for others: https://github.com/fiorix/gocp

Only tested on Linux c-shared and c-archive, and OS X c-archive. Tried FreeBSD but none are supported, and I really wanted that.

[Pieter Droogendijk]

On Thursday, June 4, 2015 at 6:36:53 AM UTC+2, Alexandre Fiori wrote:

This is cool stuff, I was playing with it a few days ago after watching Andrew's presentation.

Uploaded to GitHub so it may serve as an example for others: https://github.com/fiorix/gocp

 Select isn't that challenging, but you'll have to construct the select expression using reflect.

[hui zhang]

I am using go1.8   arm/ darwin not work ,  for both bin and archive .how  to solve that

 GOOS=darwin GOARCH=arm GOARM=7  go build -buildmode=c-archive -o libmug.a
can't load package: package .: no buildable Go source files in ....

GOOS=darwin GOARCH=arm  go build -v -o hello.ios main.go
runtime/internal/sys
runtime/internal/atomic
runtime
math
command-line-arguments
# command-line-arguments
warning: unable to find runtime/cgo.a
/usr/local/Cellar/go/1.8.1/libexec/pkg/tool/darwin_amd64/link: running clang failed: exit status 1
ld: warning: ignoring file /var/folders/cp/561_gl9j1wzd8dgv_fn5mk7c0000gn/T/go-link-691505992/go.o, file was built for armv7 which is not the architecture being linked (x86_64): /var/folders/cp/561_gl9j1wzd8dgv_fn5mk7c0000gn/T/go-link-691505992/go.o
Undefined symbols for architecture x86_64:
  "_main", referenced from:
     implicit entry/start for main executable
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)

在 2015年6月3日星期三 UTC+8下午8:34:38，Sarim Khan写道：